Various types of biomaterials are used as skin tissue restoring materials to repair skin tissue abnormalities or loss due to trauma or disease, and deformation such as congenital or acquired (age-associated) wrinkles and depressions.
For example, Patent Document 1 discloses a method in which dermal fibroblasts isolated from the skin tissue of the patient himself or herself are cultured in vitro, following which the culture is injected into skin tissue (affected site). Non-Patent Document 1 describes a method in which bovine collagen (atelocollagen) from which the C-terminal and N-terminal peptide portions have been removed to lower the antigenicity is injected at the affected site. Non-Patent Document 2 describes a method in which a hyaluronic acid gel is injected at the affected site. Non-Patent Document 3 describes a structure for implantation which is composed of pulpal fibroblasts or gingival fibroblasts adsorbed onto a substrate made of polyglycolic acid.    Patent Document 1: International Publication No. WO 97/04720    Non-Patent Document 1: DeLustro, F., et al.: J. Biomed Mater. Res. 20(1), pp. 109-120 (1986)    Non-Patent Document 2: Duranti, F., et al.: Dermatol. Surg. 24(12), pp. 1317-1325 (1998).    Non-Patent Document 3: Buurma, B., et al.: Eur. J. Oral Sci. 107, pp. 282-289 (1999).
However, because the biochemical materials (non-living tissue) described in each of the above-cited articles (Non-Patent Documents 1 to 3) are easily hydrolyzed in vivo and soon disappear from the site of administration, the advantageous effects do not persist. Also, when this type of material is used, it is difficult to completely eliminate immunological effects.
In a method like the one described in the above international publication (Patent Document 1) where dermal fibroblasts from the patient himself or herself are cultured in vitro, following which the culture is injected into skin tissue (affected site), although immunological effects do not arise, the cultured cells injected to the affected area do no more than function as a filler in the skin tissue (affected area) to be repaired. Such cells do not have a sufficient capability to actively improve the physiological state of skin tissue (physical state and/or nutritional state of skin tissue) at the affected site and in the surrounding region.